diff --git a/scripts/admin-test-env-acceptance.mjs b/scripts/admin-test-env-acceptance.mjs
index 29ac96ba3..38023a014 100644
--- a/scripts/admin-test-env-acceptance.mjs
+++ b/scripts/admin-test-env-acceptance.mjs
@@ -714,7 +714,13 @@ export class AcceptanceRun {
   addCoverageGap(module, scenario, name, reason, category = 'not-implemented', metadata = {}) {
     const nonBlocking = new Set(['device', 'external-third-party', 'visual'])
     const blocking = metadata.blocking ?? !nonBlocking.has(category)
-    this.coverageGaps.push({ module, scenario, name, reason, category, blocking, ...metadata })
+    const gap = { module, scenario, name, reason, category, blocking, ...metadata }
+    const duplicate = this.coverageGaps.some((existing) => existing.module === gap.module
+      && existing.scenario === gap.scenario && existing.name === gap.name
+      && existing.reason === gap.reason && existing.category === gap.category
+      && existing.blocking === gap.blocking)
+    if (duplicate) return
+    this.coverageGaps.push(gap)
     if (blocking) {
       this.addStep(module, `覆盖阻断：${name}`, null, false, reason,
         { scenario, deploymentBlocker: true })
diff --git a/scripts/phase4-overseas-acceptance-entry-contract.test.mjs b/scripts/phase4-overseas-acceptance-entry-contract.test.mjs
index 923f434ee..7f7355b9b 100644
--- a/scripts/phase4-overseas-acceptance-entry-contract.test.mjs
+++ b/scripts/phase4-overseas-acceptance-entry-contract.test.mjs
@@ -144,7 +144,10 @@ test('core coverage gaps fail closed while device and external-provider gaps rem
   const stepCount = run.steps.length
   run.addCoverageGap('phase3', 'device', 'Android', 'manual device validation', 'device')
   run.addCoverageGap('phase3', 'provider', 'captcha', 'external captcha', 'external-third-party')
+  run.addCoverageGap('phase3', 'device', 'Android', 'manual device validation', 'device')
+  run.addCoverageGap('phase3', 'provider', 'captcha', 'external captcha', 'external-third-party')
   assert.equal(run.steps.length, stepCount)
+  assert.equal(run.coverageGaps.length, 3)
 })
 
 test('PDA entry expands the real phase-three producer chain and builds an FBA/OVERSEAS/second-container matrix', () => {